Sometime we need install new windows.

Save the firefox ad-ons + bookmark export from Bookmarkes->manage Bookmarks -> Export

Saved password export/import

Password Exporter: Firefox ad-ons

This extension allows you to export your saved passwords and disabled login hosts using XML or CSV files that can be imported later.

Save My Documents

Check if there any Folders important in your primary Disk

Before you erase the old windows think twice if your ready and nothings loose